With fast development of wireless communications technologies, users also have higher requirements for data transmission rates. An Long Term Evolution (LTE) system can provide a high-rate data network by using a high-rate low-delay flat network architecture, so as to satisfy the increasing rate transmission requirements of the users.
In a current LTE system, a terminal device transmits information to a network device in a Transmission Time Interval (TTI) by using an uplink channel. The information generally includes data, a reference signal, Channel State Information (CSI) and the like. The CSI includes at least one of a Precoding Matrix Indicator (PMI) an Rank Indicator (RI) and a Channel Quality Indicator (CQI). The network device performs downlink scheduling on and downlink information transmission to the terminal device according to the CSI transmitted by the terminal device.
In the current LTE system, a duration of the TTI is 1 ms. To achieve a shorter round trip time and a shorter data transmission delay, a technology for shortening the TTI is put forward. However, when the TTI is shortened, the terminal device does not have sufficient uplink transmission resources for transmitting the information. Further, the network device cannot obtain the data, the reference signal, or the CSI, and therefore a downlink capacity of the system is reduced.
In conclusion, in a scenario of a short TTI, a case in which the network device cannot receive some information exists in a current method for transmitting or receiving uplink information, and further, a disadvantage that the system capacity is relatively low is caused.